In production of touch panels, electrical functions of a touch panel product need to be tested. Conventionally, devices for testing electrical functions which are commonly used have relatively large sizes. For a large-size touch panel product, a device for testing functions is expensive. In addition, it needs to test functions of a touch panel in different places. However, due to a huge volume, the conventional device for testing functions cannot meet the requirements for portability.
Therefore, there is a need for a solution of testing electrical functions which can mitigate the disadvantages described above.